1. Field of the Invention
The present invention relates to an information recording and reproducing apparatus, and particularly to a system for removing accumulated particles that have adhered to a read/write head during operation.
2. Description of Related Art
In magnetic disk devices, a lubricating oil is used for the spindle motor, voice coil motor, and other components which are contained in a housing, and during operation, the aerosol lubricating oil is floating in the housing. If the magnetic disk device is operated for a long time in such an environment, hydrocarbons, which are a component of the lubricating oil, and internally produced dust and other particles stick to the magnetic head. The accumulated particles that adhere to the magnetic head alter the floating characteristics of the magnetic head on the magnetic disk surface. Further, in magnetic disk devices employing the CSS (Contact Start Stop) starting method, hydrocarbons move around to the underside (the surface facing the disk) of the slider to cause the disk and the slider to stick to each other while the magnetic disk is stationary, hereby causing a phenomenon, referred to as stiction, which can prevent restarting rotation of the disk.
One conventional method for removing accumulated particles that have adhered to the magnetic head is an ADM (Automated Disk Monitor) method in which the magnetic disk device is stopped and restarted by the CSS starting method, and the sliding between the magnetic disk and the magnetic head is used to remove accumulated particles on the magnetic head. However, the ADM method requires that the magnetic disk device stop for 10 to 20 seconds for each operation, and it is increasingly difficult to employ this method in recent computer systems which need to operate continuously. In addition, this method cannot be used in magnetic disk devices in which the CSS method is not employed.
Published Unexamined Japanese Patent Application No. 62-229,514 discloses a magnetic disk device in which, with the magnetic head being positioned at a track, the magnetic head is vibrated by moving it in the seek direction when the data read/write operation is stopped, so as to remove the dust adhering to the slider surface of the core of the magnetic head. However, this publication does not specifically disclose the amplitude and frequency of the oscillator for vibrating the head, nor does it show a vibration mode that is effective in removing the dust.